Pramlintide is an analog of human amylin. Amylin is co-secreted with insulin from pancreatic beta cells and acts centrally to slow gastric emptying, suppress postprandial glucagon secretion, and decrease food intake. These actions complement those of insulin to regulate blood glucose concentrations. Amylin is relatively deficient in patients with type 2 diabetes, depending on the severity of beta-cell secretory failure, and is essentially absent in patients with type 1 diabetes. Through mechanisms similar to those of amylin, pramlintide improves overall glycemic control, reduces postprandial glucose levels, and reduces bodyweight in patients with diabetes using mealtime insulin. SYMLIN® (pramlintide acetate) is indicated for patients with type 1 or type 2 diabetes who use mealtime insulin and have failed to achieve desired glycemic control despite optimal insulin therapy.

Chlorotoxin I-131 is a synthetic version of a neurotoxin investigated in clinical trials for treating brain cancer. Chlorotoxin was originally isolated from the venom of the Israeli scorpion Leiurus quinquestriatus, and has potential as a tumor imaging agent based on its selective binding to tumor cells. Molecular targets for Chlorotoxin include voltage-gated chloride channels (GCC), calcium-dependent phospholipid-binding protein Annexin-2, and the inducible extracellular enzyme Matrix Metalloproteinase-2 (MMP-2). Chlorotoxin reduced the migration ability of glioma cells through tight extracellular spaces in the brain tissue by inhibition of the MMP2 because this prevented the cells from shrinking and releasing from the extracellular matrix. Chlorotoxin is a small 36-amino-acid peptide that selectively binds to glioma cells but not normal brain parenchyma. The synthetic version of this peptide has been manufactured and covalently linked to iodine 131 as a means of targeting radiation to tumor cells in the treatment of brain cancer.